To determine the correct answer for the organic compound X based on the given properties, let's analyze each option in detail. ### Properties of Compound X: 1. **Not miscible with water**: This suggests that the compound is non-polar or has a low polarity, making it less likely to interact with polar water molecules. 2. **Boiling point of 77°C**: This indicates that the compound has a relatively low boiling point, which can help us narrow down the options. 3. **Sweet odour**: Many organic compounds, especially esters, are known for their sweet smells. 4. **Insoluble in sodium hydrogen carbonate solution**: This suggests that the compound is not acidic, as sodium hydrogen carbonate (a weak base) would react with acids to produce carbon dioxide. 5. **Does not decolourize bromine water**: This indicates that the compound does not contain double or triple bonds (alkenes or alkynes), which would react with bromine. ### Analyzing the Options: #### A. Methane (CH₄) - **Not miscible with water**: True, methane is non-polar. - **Boiling point of 77°C**: **False**. Methane has a boiling point of -161.5°C. - **Sweet odour**: **False**. Methane is odorless. - **Insoluble in sodium hydrogen carbonate**: True, but irrelevant due to the other false properties. - **Does not decolourize bromine water**: True, but again irrelevant due to the other false properties. - **Conclusion**: Methane does not fit the properties of compound X. #### B. Ethanoic Acid (CH₃COOH) - **Not miscible with water**: **False**. Ethanoic acid is miscible with water due to its polar carboxylic acid group. - **Boiling point of 77°C**: **True**. Ethanoic acid has a boiling point of 118°C, which is higher than 77°C. - **Sweet odour**: **False**. Ethanoic acid has a pungent vinegar-like smell. - **Insoluble in sodium hydrogen carbonate**: **False**. Ethanoic acid reacts with sodium hydrogen carbonate to produce carbon dioxide. - **Does not decolourize bromine water**: True, but irrelevant due to the other false properties. - **Conclusion**: Ethanoic acid does not fit the properties of compound X. #### C. Ethene (C₂H₄) - **Not miscible with water**: True, ethene is non-polar. - **Boiling point of 77°C**: **False**. Ethene has a boiling point of -103.7°C. - **Sweet odour**: **False**. Ethene has a faint sweet smell but is not typically described as sweet. - **Insoluble in sodium hydrogen carbonate**: True, but irrelevant due to the other false properties. - **Does not decolourize bromine water**: **False**. Ethene does decolourize bromine water due to its double bond. - **Conclusion**: Ethene does not fit the properties of compound X. #### D. Ethyl Ethanoate (C₂H₅COOCH₃) - **Not miscible with water**: True, ethyl ethanoate is less polar than water and is not completely miscible. - **Boiling point of 77°C**: **True**. Ethyl ethanoate has a boiling point of approximately 77°C. - **Sweet odour**: **True**. Ethyl ethanoate has a sweet, fruity smell, characteristic of many esters. - **Insoluble in sodium hydrogen carbonate**: **True**. Ethyl ethanoate does not react with sodium hydrogen carbonate, indicating it is not acidic. - **Does not decolourize bromine water**: **True**. Ethyl ethanoate does not have double or triple bonds, so it does not react with bromine. - **Conclusion**: Ethyl ethanoate fits all the properties of compound X. ### Final Answer: **D. Ethyl Ethanoate** ### Summary of Key Points: - Ethyl ethanoate is a non-polar compound with a boiling point of 77°C and a sweet odour. - It is insoluble in sodium hydrogen carbonate and does not decolourize bromine water, indicating it lacks acidic properties and unsaturation. - Other options were eliminated based on incorrect boiling points, solubility in water, and reactivity with bromine. ### Revision Summary: - Understand the significance of solubility and boiling points in identifying organic compounds. - Recognize the characteristic smells of different functional groups (e.g., esters have sweet odours). - Be aware of the reactivity of compounds with reagents like sodium hydrogen carbonate and bromine water to deduce their structure. - Practice analyzing properties systematically to eliminate incorrect options in multiple-choice questions.